Process of treating vegetable oils



Patented Sept. 22, 1942 UNITED STATES 2,2963% 7 PRQWSB @F EEEAGVEGETABLE OILS TENT oFI-ICE the oils.

Foundation, West Kisdayette, End, a corporation H oi line lilo lhrag.Application February 8, i941,

. serial No. 373,660

e (lliaiuos. (oi. sea-tom) it is the object of our invention to obtain aconcentrated sterol fraction from vegetable oils,

with more special reference to soybean oil; while at the sametimereflning or partially n,

German. Process fled oil, such as one which contains a relatively smallamount or phosphatides, as is obtained by letting the crude oil standfor a while and then removing the settled-out matter, as by decanting,filtering, or centrifuging. As an example, of a soybean oil, such apartially clarified oil would show the 10110 i 1: partial analysis:

to leave behind mainly only the filter aid which was added. The solvent(say acetone) is then removed from the extract by evaporation, leavingbehind an oily residue. This usually contains irom between 2.0% and 4.5%of crude sterols in the case of soybean oils.

i. This oily residue is then treated to separate the sterols, in eitheror two ways:

a. By saponification oi the oily residue, as with alcoholic KOH or NaOH,in the well-known way to convert all the oils to soaps in the alcoholicsolution; in which soaps the sterols are somehow present, and from whichthey are re--' moved by solvent extraction, as with ether or petroleumether.

o. A modification of a: By saponification as in o, with either aqueousor alcoholic KOH or NaOH, and then adding a porositydncreasing-material, for which the sir-canes filter aids (such Per cent asiniiusorial earth or beet pulp or bran or wood volatile w pulp or paperpulp) are suitable; and then, after Phwphatides g drying ii. desired,extracting with ether or petro- Gardner break m leum ether, to dissolveout the sterols.

2. To the starting oil add a saponifying agent, i

such as sodium (or potassium) hydroxide, con-v veniently as a 10 to 14Baum solution for soy-v bean oils, with constant stirring, and heatslowly to about 140 F. and hold there for about'half an hour, continuingthe stirring. The amount of added sodium hydroxide solution may vary,but in any case it is not enough to producematerial saponiilcation ofthe oil itself. Therefore, we desirably add enough and just about enoughto neutraliz (or saponiiy) the fatty acids and to precipitate thephosphatides, while leaving the oil unsaponifle'd which usually requiresabout 0.06% to 0.10% actual NaOH inithe case of soybean oils. Then addabout 1% 01' an infusorial earth, (such as Dicalite or Celite,) as aillter aid; cool to about 80 F., with continued stirring: and thenseparate the solid matter, as by filterture sufficiently low so that thesolvent is substantially immiscible with the oil, or conducting it at ahigher temperature followed icy-cooling to that temperature ofsubstantial immiscibility. The maximum temperature for substantialimmiscibility varies with the solventfor methanol it is rather high,higher than room temperature,

ing or centrifuging, desirably in a. filter press, to

obtain a filter cake Desirably, the filter cake is well blown; so thatit is freed from the greater part of adhering oil. The oil obtained fromthe centrifuging or filtering is unsaponified; any is a nonsbreak oil,without further treatment.

3. The blown filter cake obtained by the filtering of step 2 isextracted witha suitable organic solvent for fats and oils, such forinstance as petroleum ether, acetone, or metyl-ethyl ketone; whichsolvent for fats and oils also dissolves any sterols present. Theextract thus obtained is separated from the solid residue, "as byfiltering,

while for isopropanol it is only barely above 0 C. The solvent takes upthe sterols, and a small part of the oil, and probably all or nearly allof any soaps (usually present in small amount) which may be present. Thesterolsare then in large part recovered as solids from the solvent inany of several ways-as by evaporating ofi part or all of the solvent, orby refrigerating, or by diluting with water or othersterol-precipitating liquid and then refrigerating, or by combinationsof these procedures-to leave a residual oily mother liquor. By thensaponifying this residual oily mother liquor (with either an alcoholicsolution or a water solutionyof" sodium or potas ium hydroxide), the oilis converted into soap, and the sterols present are separated from thetotal soaps present by solvent extraction as in a.

b. A modification 01 21: By proceeding as in saponification as procedureof a.

but making the final step of saponification a in s, followed by thefurther Example 1 ensues to drive of! the petroleum ether, and to leavea solid residue which consists mainly of.

crude sterols. The crude sterols thus obtained tinuing the stirring. Thesodium hydroxide neutralizes (or saponifies) the free fatty acids, andprecipitates the phosphatides: but is not sufficient in amount tosaponify the oil. -Then add 8.4 pounds of an infusorial-earth filteraid, convenientlythe one known under the trade designation of DicaliteSpecial Speedfiow. While continuing to stir, cool to about 77 F.; andthen filter the entire mass, as in a filter press, to obtain a filteredoil, which is unsaponified and "free the filter cake from adherent oil,as by blowing with air or steam, or both.

The filtered oil which we obtain is a clear, non-break, heat-bleachableoil, suitable for use wherever non-break oils are required, as forinstance in the paint and varnish industry.

The blown filter cake may be treated dried or undried. To exemplifythis, we divided the blown filter cakeinto two parts. One part wasthoroughly dried in an oven to about 0.05% moisture,

'while the other was not dried at all and contained about 5% moisture. A500-gram sample of each of these two parts (dried and undried) of thefilter cake was separately extracted with about 8 liters of acetone, infive steps, using about 1600 cc. of acetone in each step. The fiveacetone extracts for each sample were combined (but kept separate'fromthose of the other sample), and the acetone evaporated from it to leavean oily residue in each case. The oily residue thus obtained from the500 grams of the dried part of the filter cake weighed about 190 grams;and that obtained from the 500 grams of the undried part of the filtercake weighed about 228 grams. v

We took a 100-gram sample of each of these two oily residues. (bythe-procedure under paragraph 4-0. of the General Process aboveoutlined) by adding 200 cc. of 95% ethyl alcohol and 100 cc. of a 40%aqueous solution of potassium hydroxide; and refluxedthe whole for about30 minutes, after which we cooled it to about room temperature. We thenadded to each sample 100 cc. of water and 200 cc. of 95% ethyl alcohol;and we extracted the resultant soap solution five times in a separatoryfunnel with one liter of petroleum ether at each extraction, carefullydrawing off the ether after each extraction. The five petroleumetherextracts (of each sample) were combined; and the whole first washedthree times with a solution of ethyl alcohol, using about 700 cc. perwashing, and then rewashed three times with distilled water, using about500 cc. per w hing. After each washing the wash solution was allowed toseparate from the petroleum-ether layer, and drawn of! by a separatoryfunnel. Then the washed combined-p'etroleum-ether extract (for eachsample) was subjected to dis- We saponified each sample wererecrystallized from 96% ethyl alcohol.

In this manner we obtained approximately 2.11 grams of sterols from the100 grams of oily residue derived from the undried filter cake fromsoybean oil, and 2.77 grams of sterols from the .100 grams of oilyresidue derived from the dried filter cake from soybean oil.

Example 2 Other oils give somewhat similar results by the same generalprocedure, with the following results in the treatment of the oilyresidue derived from the undried filter cake:

Per cent From cottonseed oil 2.54 From corn oil 10.15 From tall oil 4.1

Example 3 and probably nearly all of any soaps which may,

be present in the oily residue. After the extraction, the extract issublectedto evaporation to drive '01! the alcohol, which leaves aconcentrate of oil that is very rich in sterols. This concentrate asderived from the dried part of the filter cake amounted to about 21grams, and contained about 2.7 grams (or about 13%) of sterols; whilethe concentrate as derived from the undried part of the filter cakeamounted to about 40 grams and contained about 2.01 grams (or about5.0%) of sterols.

In each of these two instances the sterols in the concentrate may beseparated in large measure from the oils by refrigeration. But somesterols remain in the oil. We can remove those remaining sterols, orremove all of the sterols in case we did not refrigerate it, bysaponifying the oily concentrate, and separating the sterols from thesaponified product by extraction with ether or petroleum ether asdescribed above for the first two 100-gram samples.

We claim as our invention: A

1. The process of obtaining sterols from a sterol-containingvegetableoil, which consists in adding to such oil a saponifying agent in anamount sufiicient to neutralize the fatty acids and precipitate thephosphatides but insufficient to. saponify the oil, and also adding afilter aid, then separating most of the oil from the solid matter, thenextracting said solid matter with an organic solvent which dissolvesfats and sterols,

and recovering sterols from the extract so obtained. v

2. The process of obtaining sterols from a sterol-containing soybeanoil, which consists in saponify the oil, and also adding a filter aid,then separating most of the oil from the solid matter,

then extracting said solid matter with an organic solvent whichdissolves fats and sterols, and recovering sterols from the extract soobtained.

3. The process of obtaining sterols from a sterol-containing soybeanoil, which consists in adding sodium hydroxide to such oil in theproportion of about 0.06% to 0.10% actual NaOH, and also adding a filteraid, then separating most of the oil from the solid matter, thenextracting said solid matter with an organic solvent which dissolvesfats and sterols, and recovering sterols from the extract so obtained.

4. The process of obtaining sterols from a sterol-containing vegetableoil, which consists in adding to such oil a saponifying agent in ansterol-containing soybean oil, which, consists in I said oily residue.

' 2 5. The process of obtaining sterols from. a 5

adding to such on a saponifying agent in an amount s'ufllcient toneutralize the fatty acids and precipitate the phosphatides butlnsufilcient to saponify the oil, and also adding a filter aid, thenseparating most of the oil from the solid matter, then extracting saidsolid matter with an organic solvent which dissolves fats and sterols torecover crude sterols therefrom, removing the solvent by evaporation toleave an oily residue, and recovering refined sterols from therefrom,removing the solvent by evaporation to leave an oily residue, andrecovering refined sterols from said oily residue.

NORMAN F. KRUSE. ELMER B. OBERG. WENDELL E. MANN. HENRY R. KRAYBILL.KENNETH E. ELDRIDGE.

sterols from a.

. Patent No 2,296,79

' Q ER'IYIFI GAT E 0F comcnoxl I ptember/22, 191g. NORMAN F. KRUSE, ETAL.

It 18 hereby c'ei tified that error appears 11 the pri tede'peeification ofthe above -maznflaered patent requiring eexgrecti on asrollers-g: 29.361 first column; line 57, after "gnsaponitled" insert: aaemibplon} page' 2, seem 1d.

column, 'line 17, for Per cent"- red -Per cent' aterblg and that thesaid Letters Patent .should be read with this ecu-reactiontherein thatthe same may confom to the record of the case in'tihe'Patenfi- -office.

si ned and sealed this 1st day or December, A. n. 19h2.

fienr y ven'hradal e, ('Seal) Acting Commissioner of Petemz zh.

